Young people aged from 12 to 18 consume an average of 80 g of sugar a day, of which 57.5 g comes from processed foods, higher than the WHO's recommended limit of 50 g, the Korea Health Promotion Institute said Sunday. It added that teens get 14.3 g of sugar a day from sweetened drinks.

An online survey of adolescents' lifestyle and health trends by the Ministry of Health and Welfare found that the proportion of middle schoolers who consume more than three carbonated drinks a week rose from 24.2 percent in 2009 to 27.6 percent in 2016. Among high schoolers, the proportion grew from 23.7 percent to 26.5 percent.

Overall, these teenagers drank 2.1 carbonated drinks a week and 2.8 sugary drinks when including sports drinks and juices.

Excessive sugar consumption increases the risk of obesity and chronic diseases. The proportion of overweight and obese teenagers rose from 12.2 percent in 2011 to 17.3 percent in 2016.

A study found that if sugar intake from processed foods exceeds 10 percent of the recommended daily calorie intake, the risk of obesity, diabetes and high blood pressure grows to 39 percent, 41 percent and 66 percent, respectively.

"Many teenagers get their sugar from sugary drinks, while people aged over 60 mostly consume sugar when drinking coffee," an official at the institute said. "It is best to avoid adding syrup or sugar to coffee or tea, and we recommend people get into the habit of checking the sugar content of processed foods."